Osmometry

Question 1

What is osmometry

Answer 1

Osmometry is the measurement of the concentration of solute particles in a solution based on colligative properties

Question 2

Osmometry measurements expressed in

Answer 2

osmolality (mOsm/kg of solvent)

Question 3

Principle of osmometry

Answer 3

Depend on the number of dissolved particles, not their identity.

Question 4

Osmometry equation

Answer 4

Osmomality = = φ × n × C
- φ (osmotic coefficient): Corrects for incomplete dissociation
- n: Number of dissociable particles per molecule
- C: Concentration (mol/kg solvent)

Question 5

Four properties change proportionally with osmotic pressure?

Answer 5

1. Osmotic pressure
2. Vapor pressure
3. Boiling point
4. Freezing point

Question 6

How is osmolality measured in clinical labs

Answer 6

Indirectly via colligative properties.

Question 7

what are the two common methods?

Answer 7

1. Freezing point depression (most common)
2. Vapor pressure depression

Question 9

Principle of FREEZING POINT OSMOMETRY

Answer 9

• Dissolved solutes lower the freezing point of a solvent
• Freezing point depression is directly proportional to the
  number of solute particles present

Question 11

A liquid cooled below its freezing point while remaining in a liquid state.

Answer 11

Supercooled Solution

Question 12

Triggering Freezing: Solidification begins via:

Answer 12

1. Vigorous stirring
2. Seeding (adding crystals)

Question 13

Role of thermistor

Answer 13

• Resistance decreases as temperature increases
• Temperature change detected via Wheatstone bridge circuit
• Converts temperature change into electrical signal

Question 14

relationship between solute particles and freezing point depression?

Answer 14

More solute particles → greater freezing point depression

Question 15

does the specific type of solute affect the osmometry measurement?

Answer 15

Measurement is independent of solute type

Question 16

Calibration of osmometer

Answer 16

• Uses standards of known osmolality
• Results expressed in mOsm/kg

Question 17

TRUE OR FALSE: Osmometry measures chemical
concentration, not particle concentration

Answer 17

FALSE: Osmometry measures particle concentration, not chemical
concentration

Question 18

TRUE or FALSE: Freezing point osmometry is the least widely used clinical method

Answer 18

FALSE: Freezing point osmometry is the most widely used clinical method

Question 19

Osmolality depends on __________, not molecular weight

Answer 19

number of particles

Question 20

Thermistor resistance varies with _________

Answer 20

Temperature

Question 21

What is the specific focus and principle of Proteomics?

Answer 21

• Proteins
  Principle: Analysis of the complete protein set at a given time.

Question 22

What is the specific focus and principle of Metabolomics?

Answer 22

Metabolites
Principles: Measurement of metabolite concentrations.

Question 23

Three primary techniques used to analyze the complete protein set

Answer 23

1. Mass spectrometry (MS)
2. LC-MS/MS
3. 2Delectrophoresis

Question 24

metabolite concentrations typically measured?

Answer 24

Separation techniques with MS

Question 25

Purpose of Proteomics

Answer 25

- Disease biomarker discovery - protein function analysis

Question 26

Purpose of metabolomics

Answer 26

- Detection of metabolic changes - disease states

Question 27

Application of Proteomics

Answer 27

1. Proteome profiling, 2. expression analysis, 3. PTMs, 4. protein interactions

Question 28

Application of Metabolomics

Answer 28

1. Metabolic profiling, 2. inborn metabolic disorders, 3. drug development